In the shipping industry, there often arises a need for rigid shipping containers to transport cargo in a temperature-controlled manner. For example, products related to pharmaceuticals, biotechnology, clinical trials, biologics, tissues, and derma patches not only must be transported within a specific temperature range in order to maintain the integrity of the product, but are also often required to be so transported in accordance with laws, regulations, or other guidelines. For example, the ICH stability guidelines dictate the storage conditions at which various drug products must be maintained. Furthermore, if a container is shipped from one environment to another (e.g., a hot environment to a cold environment), the external temperature forces acting on the exterior of the container may vary drastically during a single trip. Thus, there is a significant need in the market for reliable, temperature-controlled shipping containers.
Traditionally, temperature-controlled shipping containers come in two types—active temperature control and passive temperature control. Active temperature control containers can be electronically controlled devices that continually monitor and adjust the temperature of the container using, for example, compressor cooling and electric heating. These systems rely on electricity to function properly and may use dry ice as a coolant to push cool air into the payload area of the container. By contrast, passive systems are typically designed to maintain a particular temperature range for up to a predetermined amount of time, by incorporating gel packs or other types of phase change materials into the container. For example, a passive system may be capable of maintaining a given temperature range for up to 24 hours, 72 hours, or 96 hours.
Both active and passive systems have advantages and drawbacks. Passive systems are only good for a generally shorter, predetermined amount of time and must be configured properly with the right materials based on the requirements of the payload. However, active systems are typically much more expensive, and because they rely on a power source, they present a risk of damage to the payload if the power source supporting the container goes down.
Thus, it would be desirable to develop an improved passive temperature-controlled container for regulating a payload's temperature within a specified range, for an extended period of time, that can be achieved inexpensively compared to other solutions.